Soil Properties

Cyclic1D has 15 predefined materials that the user can choose from. Basic model parameter values for these 15 materials are listed below.

Cohesionless Soil Shear wave velocity at 10m depth1,2 (m/s) Friction angle3 (degrees) Possion's ratio Permeability coeff.4 (m/s) Mass density5 (kg/m3)
Loose, silt permeability 185 29 0.4 1.0x10-7 1.7x103
Loose, sand permeability 185 29 0.4 6.6x10-5 1.7x103
Loose,  gravel permeability 185 29 0.4 1.0x10-2 1.7x103
Medium,  silt permeability 205 31.5 0.4 1.0x10-7 1.9x103
Medium,  sand permeability 205 31.5 0.4 6.6x10-5 1.9x103
Medium,  gravel permeability 205 31.5 0.4 1.0x10-2 1.9x103
Medium-dense,  silt permeability 225 35 0.4 1.0x10-7 2.0x103
Medium-dense,  sand permeability 225 35 0.4 6.6x10-5 2.0x103
Medium-dense,  gravel permeability 225 35 0.4 1.0x10-2 2.0x103
Dense,  silt permeability 255 40 0.4 1.0x10-7 2.1x103
Dense,  sand permeability 255 40 0.4 6.6x10-5 2.1x103
Dense,  gravel permeability 255 40 0.4 1.0x10-2 2.1x103
Cohesive Soil Shear wave velocity (m/s) Undrained shear strength6 (kPa) Possion's ratio Permeability coeff.4 (m/s) Mass density5 (kg/m3)
Soft 100 18.0 0.4 1.0x10-9 1.3x103
Medium 200 37.0 0.4 1.0x10-9 1.5x103
Stiff 300 75.0 0.4 1.0x10-9 1.8x103
U-Clay/Rock User-defined Used-defined 0.4 1.0x10-9 User-defined

Base Boundary Condition

Bed rock type Shear wave velocity7 (m/s) Mass density (kg/m3)
Rigid base Infinite N/A
Soft rock 700 2.5x103
Medium rock 1100 2.5x103
Hard rock 1600 2.5x103
Total transmitting Same as bottom layer Same as bottom layer
U-Rock User-defined User-defined

1. Shear wave velocity of cohesionless soils varies approximately in proportion to (pm)1/4 where pm is effective mean confinement.

2. Shear wave velocities for cohesionless soils are based on the empirical formula of Seed, H.B. and Idriss, I.M. (1970). "Soil moduli and damping factors for dynamic response analyses," Report EERC 70-10, Earthquake Engineering Research Center, University of California, Berkeley.

3. Friction angles for cohesionless soils are based on Table 7.4 (p.425) of Das, B.M. (1983). Advanced Soil Mechanics, Taylor and Francis Publisher.

4. Permeability values are based on Fig. 7.6 (p.210) of Holtz, R.D. and Kovacs, W.D. (1981). An Introduction to Geotechnical Engineering, Prentice Hall, Englewood Cliffs, New Jersey.

5. Mass density is based on Table 1.4 (p.10) of Das, B.M. (1995). Principles of Foundation Engineering, Third Ed., PWS Publishing Co., Boston, MA.

6. Undrained shear strength for cohesive soils are based on Table 7.5 (p.442) of Das, B.M. (1983). Advanced Soil Mechanics, Taylor and Francis Publisher.

7. Shear wave velocities for rocks are based on International Code Council (1998). 2000 International Building Code (Final Draft).